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Mojo Surf Ballast Setup

As mentioned in many posts this year, our family REALLY enjoyed surfing behind our 2012 Mojo this season! With help from Moombadaze and Spencer from Wakemakers and stealing ideas from lasvboombox, by the end of the season we got the ballast system figured out. I believe that this setup will work for the 2013 Mojo as well as the 2013 LSV.

My objectives for the system were as follows:

1) Provide a "better than good" regular surf wave.

2) Entirely hidden.

3) No additional pumps, drilling into the hull, etc.

4) Controlled from the driver's seat.

5) Reasonable fill time.

Using a tsunami pump & throwing bags around the boat for the first half of the season, we found the best wave was achieved by weighting the boat as follows:

1) 1,100 lb sac full in port locker

2) 370 lb "tube" sac full under port seats

3) 1,100 lb sac about 40% full in starboard locker

4) 450 lb stock, center hard tank full

5) 650 lb bow sac full

Yep, that's just over 3,000 lbs of ballast. The 345hp Indmar surf motor has no problem getting the Mojo up on plane.

Here is an overview of the system I set up. The blue are fill lines, and the red are vent lines.

The port (or left "L") pump fills/empties the port 1,100 and 370 tube sac. The fill line is simply "T'd" and the line for the 370 runs under the 1,100. The 370 is vented back into the top port on the 1,100 and the 1,100 is vented thru a check valve out the side of the boat. If I do not want to use the 370, I filled a connection with epoxy and can easily cap the fill ine off.

The starboard (or right "R") pump fills/empties the starboard 1,100 sac. No mods done to the factory fill and simply added a check vavle to the vent line.

The center ("C") pump fills/empties the center hard tank and the IBS. At the point the factory tank vent lines runs out from under the floor in the bow storage, I installed the Bosworth directional Y valve. If I choose not to run the IBS, I can vent the center tank out the side. If I want to run the IBS, I rotate the valve and the center tank vents into the IBS. The IBS vent line is "Y'd" back into the factory vent line with a check valve installed.

First install step was the port locker plumbing. After some experimentation of using the port pump for the 1,100 and the starboard pump for the 370 tube, I realized that the boat really needs some weight in the off side to get a great wave. I also realized that by designing the system where the center vent would fill the IBS, that my fill time was going to be dictated by that total 1,100 lbs so running the 1,100 locker bag and 370 tube together wasn't going to cost me too much additional time.

pic from inside port locker towards bow and fill line hooked up to 370 tube sac

Plug installed at the end of the 370 fill line. I thought this was a simple solution vs another valve. We keep it in the glovebox for when/if it's needed.

Note the boo-boo on my thumb above! That was the result of NOT being patient and waiting for the hair dryer to heat up the tubing well and instead trying to push, twist and muscle crank it on. Take your time and let the tubing heat up, then have some towels or light gloves on to work the tubing over the fittings.

Starboard side was next and was easiest as all I did was install a check valve on the vent line.

Finish it up with the IBS. I cut the factory center hard tank vent line just as it comes out of the floor in the starboard bow storage area. It's tight in there and the Mojo storage compartments are deep. So, another word of caution, have somebody around to pull you're fat arse outta there. I was on my back installing the check valve & vent line and popped right into that hole. I had to wiggle and squiggle to get turned back around to get out of there. You may also want to start with the bow so you're not too many beers into the job.

I pre-measured all my lines and installed the IBS fill and the vent lines to the valve before attaching the valve to the center vent line. From the left is the vent line if you're only using the center tank and no IBS, from the middle is the fill to the IBS and from the right is the incoming center tank vent/fill line.

everything hooked up.

The vent off the top of the IBS is tricky. Since the center hard tank vent is a 1 in line, you need to order a 1 inch Y connector (it's listed as 1 1/8 in on Wakemakers) and a 1 in check valve. I missed that it was 1 in the first time and ordered all 3/4 in parts. Sorry for the bad pic below, but you can see the larger check valve leading to the thru hull vent. That is the only connection I put a hose clamp on. I thought "just in case" it would be easier to get to remove that versus a crimped connection.

pic of the IBS installed, but not filled. It had been filled as you can see from the missing cupholders. I ordered the bow cushion which means these are normally covered anyway, so no worries.

The vent off the top of the IBS is tricky. Since the center hard tank vent is a 1 in line, you need to order a 1 inch Y connector (it's listed as 1 1/8 in on Wakemakers) and a 1 in check valve. I missed that it was 1 in the first time and ordered all 3/4 in parts. Sorry for the bad pic below, but you can see the larger check valve leading to the thru hull vent. That is the only connection I put a hose clamp on. I thought "just in case" it would be easier to get to remove that versus a crimped connection.

Going to order some check valves today. My boat is not here at the house to measure, so does the 2013 have 1" hose or 3/4? or is the 1" only on the center tank?

The space you have in there even with the 1100 full blows me away... When experimenting did you ever stack any more sacs in there to max it out and see what effect it had on the wave?

There isn't a ton of room left on top to stack anything significant, IMO. I've thought about strapping one of the stock bags to the port seats or on top of the sun pad and the other under the bow cushion, but don't really like the thought of having to mess with the dang handheld tsunami.